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The concentrations of Cd, Cr, Cu, Pb, Zn in soil, wheat and vegetable samples from sewage irrigated farmland in Xi’an, Shaanxi Province, were determined. Results indicated that average contents of Cd and Pb in the research area were higher than soil background values in Xi’an and Shaanxi Province, respectively, and the average contents of Cu and Zn were higher than soil background values in Shaanxi Province, respectively. Significantly positive correlation was found between Cd and Pb in soils, while highly significant positive correlation was found among Cr, Cu and Zn, respectively. The principal component analysis showed Cd and Pb in soils were associated with anthropogenic activities, whereas Cr, Cu and Zn were predominantly controlled by parent material. The quality of soils were evaluated with potential ecological risk index and Nemerow pollution index, however, both of the results showed that Cd was the major pollution element in soil. In the study areas, exceeding rates of Cr and Pb in wheat samples were up to 70.00% and 80.00%, respectively; exceeding rates of Cd, Cr, Pb in fruit vegetable samples were 66.67%,100% and 66.67%, respectively; and exceeding rates of Cd, Cr, Pb in flower and leaf vegetables samples were 100%. Therefore, it was suggested that farmers should avoid cultivating high transfer factor plants, such as flower and leaf vegetables, meanwhile, sewage with Cd must be purified strictly before irrigation.